Well-drill jar



L sept. 76, 1930. F. A. F'iELDs WELL DRILL JAR Filed June 12, 1928 im jy f PatentedSept. 16, 1930 PATENT oFFrcE :aan n. imams, or' mrm, onnnon WELL-DRILL :n

Application led .Tune 12,

This invention appertains to improvements in well drill appliances generally2 and more particularly to a means for jarrmg a drill to facilitate its removal from the bore of 5 a well.

The purpose f this invention is to aid in the drilling of wells, particularly for oil and gas, which often re uires the drilling to be carried to depths o several thousand feet t or more. After a drilling operation has been started, it very often becomes necessary to withdraw the drill from a well bore, and, in doing so, the drill bit or tool will become fast in the bore, so that the drill cannot be finally withdrawn without a great expenditure in time, labor and effort, unless the drill be jarred back or downwardlyv of the drill bore for the purpose. This backward or downward movement of the drill to free the $0 bit or tool for further and final withdrawal has heretofore been accomplished mainly by driving on the upper end of the to jar the drill bit or tool loose from the retarding accumulation of dirt, which gathers on top of the drill bit or tool from the walls of the well bore. This driving on theidrill pipe is a very unsatisfactory method of freemg a drill bit or tool, particularly as the depth of the well bore increases and the drill pipe is correspondingly lengthened, since with the longer drill ipes it becomes almost impossible to drive t e same because of the spring occurring driving force applied thereof.

.An object of the invention is, therefore, to

rovide a means of the class set forth which 1s of a comparatively simple but durable and eilicient construction and arrangement' of parts, and which is of a nature to be readily incorporated in or applied to a drill pipe line for effectively jarring the drill bit or tool carried by the latter, and otherwise facilitating the freeing of the bit or tool-for its subsequent withdrawal from the bore of to the upper end a we Another obj ect of the invention is the .provision of a device or appliance, as hereinbefore characterized, which will include a means whereby the drill bit or tool may be drin pipetherein under the 1928. Serial I0. 284,710.

rotated in either of its directions of movement, in going into the well bore', or in being wlthdrawn therefrom, as a further aid to the proper and desired easy and less laborious manipulation of the drill throughout a drilling operation.

With the foregoing and other equally important objects and advantages in view, the invention resides in the certain new and u'seful combination, construction and arrangement of parts as will be hereinafter more fully described, setforth in the appended claims, and illustrated in theaccompanying drawing, in which:

Figure 1 is a fragmentary side elevation of the lower end portion of a well drill pipe assembly embodying the present invention, andas it appears within the lower end of a well bore,

Figure 2 is an enlarged fragmentary vertical longitudinal section through the assembly aforesaid, and showing the osition of the parts thereof at the end -o a jarring stroke of the appliance,

Figure 3 is a view similar to that in Figure 2, but shows the position of.the parts with the jar appliance raised and ready to deliver a downward stroke, l

Fi'gure 4 is a horizontal section taken on -the line 4-4 of Figure 2, and

Figure 5 is a similar section taken on the line 55 of Figure 2. j

Referring to the drawing, wherein like characters of reference designate corresponding parts throughout the several views thereof, the embodiment of the appliance2 as shown therein by way of example, comprises a jar unit 10 to be coupled into the drill pipe assembly at a point above the drill bit or tool a at the lower end of the drill pipe assembly. In this instance of the invention, as illustrated, the drill bit or tool a is joined by a tapering tool joint connection b to the lower end of a drill pipe section c, which, in turn7 is joined at its upper end by means of a tapered tool joint connection d to the lower end of an upper drill pipe section e. Similarly, the upper end of the intermediate drill pipe section e is joined by means of a tapering tool joint connection f to the ,lower end of the jar l unit 10, lwhile the upper end of the latterl is, in turn, joined by means of another tapering tool joint connection g to the lower end of an upper drill section it.

The drill jar unit per se, forming the subject matter of the invention, comprises an outer tubular member or barrel 11, having its lower end portion 12 inwardly thickened about a central longitudinal bore or water course 13, which opens at its upper end through a substantially conical shoulder 14 at the lower end of a relatively short, but slightly enlarged, circular bore 15. Above the bore 15, the interior of the member or barrel l1 is formed to provide a squared bore 16, of a greater cross sectional area than that of the circular bore 15, and above this intermediate or square bore 16, the interior is further enlarged to provide another circular bore 17.

inserted downwardly of the upper open end of the outer tubular member or barrel 11 is an inner working barrel 18, which has a bore or water course 19 extending longitudinally through the same, and of equal diameter to that of the bore or water course 13 in the lower thickened end portion 12 of the outer member or barrel 11. The extreme lower end ortion 20, of the inner barrel 18 is of a re uced cylindrical form, and of a diameter to snugly seat in the reducedbore portion of the outer member or barrel 11, and the longitudinal bore 19 opens centrally through the end face of this reduced portion, which face is formed with a substantial conical depression 21 to seat on the conical shoulder 14, when the inner barrel 18 is in its lowest position.

Immediately above the reduced cylindrical vportion 2 0,` the working barrel 18 is formed to provide a squared portion 22 of a length corresponding to that of the squared portion 16 of the outer member or barrel 11. i he lower shouldered end of the squared portion 22 is preferably bevelled, as at 23, to conform to the similarly Ybevelled shoulder 24, formed at the lower end of the squared bore 16, so that a substantial bearing surface between the parts is rovided for at this point. Spaced at a slig t distance above the upper end of the squared portion 22 is an annular member or jar element 25, which is carried by or formed with the working barrel 18, and this member or element is of a diameter to have snug sliding engagement with the upper enlarged bore 17.

Threaded into the u per end o'f the enlarged bore 17 is a stu ng box 26, which is engaged over the upper projected end portion of the inner barrel 18, and similarly threaded into the up r end of this stuno box is a gland 27. ith a packing place within the stuffing box 26, the gland 27 will be tightened inwardly againstv the packing, and will expand the same to prevent leakage .of the well bore,

between the parts. A am ring or nut or the like 28 may be employed on the upper end of the stuffing box to cooperate with the flanged portion at the upper end of the gland 27, if desired.

In the operation of the appliance, as thus constructed, arranged and assembled, the drill and drill pipe assembly in which the drill jar has been incorporate ,will function in the usual manner of such device to drill a well bore, and water will be discharged downwardly of the alined bores or courses of the several drill pipe sections, and the jar unit to the drill bit or tool a, as required or necessary.

In the event of it being expedient that the drill bit or tool a be withdrawn upwardly the lifting of the same will be accomplished with the ordinary hoisting rig. However, in the initial lifting movement of the drill pipe, the inner barrel 18 of the jar unit or appliance, will move upwardly relative to the outer member or barrel 11, and until the annular jar member or element abuts the lower end of the stung box 26, when the weight of the lower drill pipe sections c and e, the drill bit or tool a and their couplings, will be borne directly by this annular jar member or element. In the upward movement of the inner barrel 18, the annular jar member or element 25 forcibly strikes the lower end of the stuffing box 26, and thereby jars the drill bit or tool a free from its penetrating engagement with the bottom of the well bore.

When, in the course of the lifting movement of the drill assembly, the drill bit or tool a becomes fast to the well bore, due to the packing of loosened dirt from the wall of the latter above the same, it will be readily jarred back toward the bottom of the well bore by releasing the upper drill pipe sections and the inner barrel 18 at the lower end thereof, the dropping of which sections and the inner barrel causing the latter to suddenly move downwardly to the lower end of the outer barrel 11. As the inner barrel 18 drops downwardly of the inner barrel 11, the lower shouldered portion 23 forcibly strikes the shouldered ortion 24 at theM lower end of the squared ore 16 of the outer barrel, while the blow thus struck will be somewhat cushioned by the compression of iuid within the upper enlarged bore 17 beneath the annular jar member 25. Should the first blow or stroke of the inner barrel 18 fail to dislodge the drill bit or tool a, the workin@r stroke of the same will be re` peated in a l1 e manner, as aforesaid, until the drill bit or tool is free from further liftlng movement. To further facilitate the removal of the drill bit or tool a from the insertion of the same back into a well bore, it, together with the lower drill pipe sections c and e, may be rotated through the clutch imA ion

connection of the squared portion 27 of the inner barrel 18 with the squared bore 16 of the outer barrel 11. These squared porti'ons 27 and 16 areengaged at all times, so that a rotary movement may be impartedto the parts throughout the operation of the drill assembly.

Without further description, it is thought that the features and advantages of the 1n- ,o vention will be readily apparent to those skilled in the art, and it will of course be understood that changes in the form, proportion and minor details of construction may be resorted to, without departing from the spirit of the invention or its scope as claimed. 4

Having thus fully described the invention, what is claimed is: v

1.. A rotary drill jar comprising an outer hollow barrel open at its upper end and having its interior formed to provide a lower squared bore portion and an upper cylindrif cal bore portion, a working barrel mounted for relative reciprocating jarring movements inwardly of the upper open end of said working barrel, a squared jar portion carried by said working barrel and engaged in the lower squared bore portion of said outer barrel, an annular jar member carried by said working barrel and operable within the upper cylindrical bore portion of said outer barrel, said annular jar member being cushioned on its v down stroke within the said cylindrical bore portion, and a stuffing box seated in the upper open end of said outer barrel and adapted to be struck by the annular jar member inthe y upward movement thereof.

2. A rota drill jar comprisin an outer hollow barre open at its upper en and havin its interior formed to provide a lower cy indrical bore portion, an intermediate square bore portion and an upper enlarged cylindrical bore portion, a working barrel mounted for relative jarring movements inwardly of the upper o en end of said working barrel, a reduce cylindrical portionl formed at the lower end ofl said working barrel and engageable with the lower of the said cylindrical bore portions, a squared portion carried by said working barrel and engaged in the squared bore portion of said outer barrel, the shoulders at the lower end of said squared portion having striking engagement with the lower end of the said squared bore portion, an annular jar meml ber carried by said workin barrel and operable within the uppr cylindrical bore portion of said outer arrel, said annular jar member being cushioned on its downward 6o stroke within the said cylindricalbore portion, and a stuiiing box seated in the up er4 open end of said outer barrel and adapte to be struck by the annular ar member in the upward movement thereo $5 Y FRED A. FIELDS. 

